Vacuum pump



July 14, 1931. M. L. NESTAL VACUUM PUMP Filed Aug. 1, 1928 IN VEN TOR. m qzzm 4'. fizzs'rqz A TTORNEY Patented July 14, 1931 UNITED STATES PATENT FF-WE MAR-GELINO L. NES'IAL, OF SAN DIEGO, CALIFORNIA VACUUM PUMP Application filed August 1, 1928, Serial No.

My invention relates to vacuum pumps, more part-icularly to pumps to be used in connection with refrigeration, vacuuln devices, cow milkers, and other domestic and commercial use, and the objects of my invention are: First, to provide a vacuum pump which is oil sealed therefore reducing the leakage to a minimum; second, to provide a vacuum pump of this class which is double acting; third, to provide a vacuum pump of this class which is encased in an oil tight casing in which the pump is positioned; fourth, to provide a pump of this class in which oil is admittedfto the cylinders and pistons and other parts and mixes with the air for operating the pressure valves and is mostly expelled with the air with each movement of the pistons and fifth, to provide a pump of this class which is very simple and econom cal of construction, eflic1ent 1n 1ts action, durable, and which will not readily deteriorate or get out-of order. With'these and other objects in view as will appear hereinafter, myinvention consists'of certain novel features of construction,}combination and arrangement of parts and portions as will be hereinafter described in detail and particularly set forth in the appendedv claims, reference being hadto the 30 accompanying drawings'and to the characters of reference thereon which form a part of this application in which: 7 i Figure 1 is a longitudinal sectional view of my pump through the middle thereof showing certain parts andfportions in elevation to facilitate the illustration; Fig. 2 is a sectional view at right angles'thereto through 21-2 of Fig. 1 showing some of the parts and portions in elevation to facilitate the illustration; Fig.3 is a sectional-view through of Fig. 1, and Fig. 4 is a sectional View through ofFig. 1.

Similar characters of reference refer to similar parts and portions throughout the several views of the drawings.

The base 31 journal support 2, casing 3,

Pump cylinder 4:,pump cylinder head 5, piston 6, packing support 7, hollow pistonrod 8,valve,;9 adjustab1e .oil intake member 10,

50 journal member l1,va1ve member 12, spring 296,773, and in Mexico January 20, 1928.

13, auxiliary cylinder 14, nipple 15, valve seat bushing 16, valve 17, valve rod 18, pres sure disc 19, inlet tube 20, connecting rod 21, disc 22, shaft 23, fly wheel disc 24, and handle 25, constitute the principal parts and portions of my vacuum pump.

The base 1 is relatively rigid and is provided with a hole 160 in one side thereof. Mounted on this base 1 is a support 2 which is rigidly secured thereto and extends upwardly at the'one end thereof. On the opposite end of said support 2 is a journal member 2a which serves as a journal for the'shaft 23. Mounted on this base 1 centrally over the hole 10; and adjacent the support 2 and ournal 2a is a casing 3 which is a liquid tight casing at its lower portionand is adapted to hold oil which is preferably about the level of the line 3a in said casing. Mounted in the lower end of this casing is the pump cylinder 4 shaped as shown best in Figs. 1 and 2 of the drawings, and provided with ports 4a and therein. Itis provided in its normal lower enolwith a head 5 which is screwed into the lower end thereof forming a tight joint. This head 5 is provided with a downwardly, extending screw threaded portion 5a which extends through the hole 1a in the base 1 and through a similar hole in the casing 8 and on the under side is provided a nut thus pro.- viding. means for rigidly securing the casing as well as the cylinder to the base 1 and also forming a tight joint between the casing and cylinder.

Reciprocally mounted in this cylinder l is a hollow piston 6 which is formed of-several members; the members 6a and 67) forming the main portion of the piston. They are held in certain spaced relation .to each other by means of the packing retainer 7., Interposed between the sides of this member 7 and the members 6a and 6b are packing mem} bers 7a which extend out past the edges of the members 6a, 6b and 7 and seal the joint between the piston and cylinder. The mem her 600 is provided with a hole therein in which. is reciprocally mounted a valve member 9 which is preferably a gravity actuated valve member, the small portion of which is spider shaped to permit the vacuum flow ton 3 a threaded portion'14a.

therethrough. Secured centrally in the member 6?) is a hollow piston rod 8 which extends upwardly through an opening in the cylinder 4, said opening 40 being considerably larger than the piston rod 8 to permit the vacuum flow therethrough. Mounted on the upper surface over said opening 40 is a valve bushing 12 which is adapted to open and close said opening 40 with the upward and downward movement of the piston 6. The piston rod is supported by a ournal 11 which is secured to the cylinder by means of screw-s 11a, shown bestin Fig. 2 of the drawings. interposed between this journal and the valve member 12 is a spring 13 tending to hold said valve member 12 seated. ln the upper end of the piston rod 8 are ports 8a which open out into the interior of the casing to permit the vacuum flow. Pivotally connected to the upper end of the piston rod 8 is a connecting rod 21, the other end of which is pivotally connected to the disc 22 by means of a bolt 22a. This disc is secured on a shaft 23 revolubly mounted in the journal 20:. Sec .red on the outer end of the shaft 25 is a fly-and hand wheel 24 which is provided with a handle 25 to facilitate its being turned by hand. Mounted in the periphery of said wheel is a groove 24a which is adapted to serve as a belt groove so that the wheel may be turned by power, such as a motor, engine, or the like.

In the cylinder walls at one side is a port 460 which is provided with two connecting ports 4d and 46. The port 4e is adapted to admit the vacuum pressure above the piston 6, while the port 463 is adapted to admit the vacuum pressure below the piston 6, thus providing for double action of the piston in the cylinder in its upward and downward movement therein. This port 4a extends upwardly and communicates with an opening 4f in the upper portion of which is mounted an auxiliary cylinder 14 secured by means of This cylinder is provided with a port 146 leading from the c o enin 4 to the interior of said 0 linder.

The upper end of this auxiliary cylinder 14 is internally threaded and mounted therein is a tubular member 20 which extends up wardly through the upper end'of the casing 3 and into the upper end of which may be connected a hose or othermedium for connecting with any receptacle in which it is desired to provide a vacuum. Mounted in this tube 20 at the lower end in the center is a nipple member 15 which is provided. with outwardly extending ports 15a and centrally in this nipple is a bushing seat member 16. In the lower end of this member 15 is an opening in which is reciprocally mounted a valve stem 18 upon the upper end of which is mounted a valve member 17 which is adapted to engage the lower valve seat portion of the member 16 when raised to a certain position.

Secured on the lower end of this valve stem 18 is a pressure disc 19.

In the cylinder 4 is provided a port 46 which communicates with the interior of the cylinder by means of a port 49. This port 49 is so positioned that it will admit oil through the port 4?) toeither the upper or lower side of the piston 6 depending upon the position of the piston at the ends of its inward and outward strokes. The upper end of said port 412 communicates with the exterior of the cylinder 4 through a port 4h and communicating therewith is an adjusting screw 10 which is adapted to adjust the quantity of liquid adapted to pass from the interior of the casing into the interior of the cylinder.

This adjusting screw 10, it will be noted, is supported by a tension spring 10a which tends to prevent its loosening or turning and getting out of adjustment.

The operation of my pump is as follows: It will be noted that the casing 3 is filled with oil to a level about even with the dotted line 3a in Fig. 1 of the drawings so that all the working parts of the vacuum pump are sealed in this oil. Upon the upward stroke of the piston to the position shown in Fig. 1 of the drawings, air is-drawn through the tube20, past the'valve seat member 16, thevalve 17 having dropped below the port openings 15a, then out these openings 15a through the port 14b, openin g 14/, ports 4a, and ports 465 to the cylinder. At the same time air above the piston 6 is forced out through the opening 46 raising the valve 12 and forcing the air out through the oil in the casing 3 where it raises to the top of the oil and passes out. Then on the downward movement ofthe piston the air accumulated in the lower portion of the cylinder is forced past the valve 9, out through the stem 8 and ports 8a into the oil in said casing and rises to the top. During the initial downward movement of the piston the valve 17 is forced to the seat 16 by the gas velocity against the disc 19 and held there by gas pressure, thus sealing the tube 20 against back pressure. V

Though I. have shown and described a particular construction, combination and arrangement of parts and portions, I do not wish to be limited to this particular construction, combination and arrangement but desire to include in the scope of my invention the construction, combination and ar rangement substantially as set forth in the appended claims. Having thus described my invention, What I claim as new and desire to secure by Letters Patentis: I

1. In a vacuum pump, in combination a casing with a fluid therein, a cylinder mounted in said casing in said fluid, a piston reciprocally mounted in said cylinder, a valve in connection with one side of said piston,

and an outlet port in connection with the opposite side thereof, an auxiliary cylinder communicating with said cylinder, a con ductor connecting with said auxiliary cylinder, a valve between said conductor and said auxiliary cylinder, a pressure actuated member for operating said valve and means for operating said piston.

2. In a vacuum pump, in combination a casing with fluid therein, a cylinder immersed in said fluid provided with a port communicating with the interior of said cylinder, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve communicating with the lower side of said piston, a hollow ported piston rod connected with the upper side of said piston, a conductor communicating with the cylinder, the gas in the chamber in which the vacuum is to be formed being conducted through the conductor to the cylinder for causing vacuum in the chamber, pressure actuated means in association with the cylinder and conductor for admitting rarified gas from the conductor to said cylinder through said port, and means for reciprocating said piston.

3. In a vacuum pump, in combination a casing with oil therein, a cylinder immersed in said oil secured in the lower end of said casing provided with a port communicating with the oil in said casing and another port communicating with the interior of said cylinder and extending upwardly therein, an auxiliary cylinder communicating with said port, velocity and pressure control means in said auxiliary cylinder communieating with the exterior of said casing near the upper end thereof, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve in the lower side of said piston, a hollow piston rod communicating with the interior of said piston with ports near the upper end of said piston rod, means for operating said piston and means for regulating the flow of oil through said port to said cylinder.

i. In a vacuum pump, in combination a casing with oil therein, a cylinder immersed in said oil secured in the lower end of said casing provided with a port communicating with the oil in said casing and another port communicating with the interior of said cylinder and extending upwardly therein, an auxiliary cylinder communicating with said port, velocity and pressure control means in said auxiliary cylinder communicating with the exterior of said casing near the upper end thereof, a hollow piston reciprocally mountcd in said cylinder, a pressure actuated valve in the lower side of said piston, a hollow piston rod communicating with the interior of said piston with ports near the upper end of said piston rod, means for operating said piston, means for regulating the flow of oil through said port to said cylinder, and valve controlled outlet means from said cylinder around said piston rod from the upper side of said piston.

.5. In a vacuum pump, in combination a casing with oil therein, a cylinder immersed in said oil secured in the lower end of said casing provided with a port communicating with the oil in said casing and another port communicating with the interior of said cylinder and extending upwardly therein, an auxiliary cylinder communicating with said port, velocity and pressure control means in said auxiliarycylinder communicating with the exterior of said casing near the upper end thereof, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve in the lower side of said piston, a hollow piston rod communicating with the interior of said piston with ports near the upper end of said piston rod, means for operating said piston, means for regulating the flow of oil through said port to said cylinder, valve controlled outlet means from said cylinder around said piston rod from the upper side of said piston, and a base and support for said casing and piston operating means.

6. In a'vacuum pump, in combination a cylinder provided with a port communicating with said cylinder at opposite sides oi": its middle, a second port communicating with the interior of said cylinder on the op posite sides of its middle, velocity and pressure controlling means for admitting air into said port from the exterior of said casing, means to r re 'ulatingthe size of said secondary port, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve communicating with the lower side of said piston for regulating the. flow of air from the lower side to the interior of said piston, a hollow piston rod communicating with the interior of said piston and extending upwardly through the walls of said cylinder leaving an opening around said piston rod, a valve for controlling the flow of air from said cylinder through said opening, means for operating said piston.

7. In a vacuum pump, in combination a cylinder provided with a port communicating with said cylinder at opposite sides of its middle, a second port communicating with the interior of said cylinder on the opposite sides of its middle, velocity and pressure con trolled means for admitting air into said port from the exterior of said casing, means for regulating the size of said secondary port, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve communicating with the lower side of said piston for regulating the flow of air from the lower side to the interior of said piston, a hollow piston rod communicating with the interior of said piston and extending up wardly through the walls of said cylinder leaving an opening around said piston rod,a valve for controlling the flow of air from said cylinder through said opening, means for operating said piston, a connecting rod connecting with said piston rod, a disc Wheel pivotally connected with said connecting rod near one side thereof, a shaft supporting said disc wheel and another disc Wheel on said shaft provided with a handle.

8. In a vacuum pump, incombination a cylinder provided With a port communicating with said cylinder at opposite'sides of its middle, a second port communicating with the interior of said cylinder on the opposite sides of its middle, Velocity and pressure controlled means for admitting air into said port from the exterior of said casing, means for regulating the size of said secondary port, a hollow piston reciprocally mounted in said cylinder, a pressure actuated valve communicating with the lower side of said piston for regulating the flow of air from the lower side to the interior of said piston, a hollow piston rod communicating with the interior of said piston and extending upwardly through the walls of said cylinder leaving an opening around said piston rod, a valve for controlling the flow of air from said cylinder through said opening, means for operating said piston, a connecting rod connecting with said piston rod, a disc wheel pivotally connected with said connect-- ing rod near one side thereof, a shaft supporting said disc wheel, another disc wheel on said shaft provided with a handle, and a belt groove in the periphery of said disc Wheel.

In testimony whereof, I have hereunto set my hand at San Diego, California, this 14th day of July, 1928.

MARCELINO L. NESTAL. 

